376 On the Fecundation of the Egg in the Common Fowl. 



resumed to a smaller extent. When the hen sits, the oviduct 

 is much reduced and loses its ciliated epithelium. 



I have stated that the right-hand lobe of the infundibulum 

 was generally more abundantly supplied with pits and bags 

 than the left ; and a similar difference is observed also with 

 regard to the turgescence and luxuriant growth of the parts 

 generally. The portion most affected is the anterior part of 

 the right lobe, near the pointed part which stretches along 

 the anterior mesometry towards the ovary. Here the right 

 lobe always develops a more or less expanded, almost rect- 

 angular secondary lobe ; at the same time, in the highly 

 turgescent state, the pitted zone is arched inwards against tlie 

 anterior narrower part of the infundibulum. Thus a kind of in- 

 dentation is formed between the turgescent lobe and the narrow 

 anterior part of the infundibulum. This indentation corresponds 

 in size to the stems of the folliculi, and catches round them, 

 collar-like, when the infundibulum has seized the follicle. 

 The expanded right lobe then closes round the follicle in the 

 shape of a cupola and pulls against the contractions of the 

 mesometry, by which the ripe follicle and in part the ovary are 

 drawn backward — a process which no doubt contributes to the 

 bursting of the follicle. Only one case has occurred to me in 

 which the left side of the infundibulum was more developed 

 than the right. 



I believe myself justified in concluding that this pitted zone 

 serves to arrest the progress of the semen and to preserve it — 

 in short, that it constitutes a true receptaculum seminis — and 

 that the fecundation of the eggs takes place in the infundi- 

 bulum, on the egg coming into contact with the semen by the 

 bursting of the follicle. Not having met with living semen in 

 the pitted zone later than the twelfth day after the pairing of 

 the hen, I assume that it does not generally keep longer ; and it 

 is in good keeping with this view that fertile eggs, according to 

 Coste's and my own experiences, are not often laid after the 

 eleventh day, though instances have occurred of the last fertile 

 &gg being laid on the seventeenth or eighteenth day. But 

 in these cases the hens have not been laying regularly ; and 

 though a successful pairing has been known to suffice for 

 eight fertile eggs, its efficacy generally reaches only to five 

 or at most seven, the subsequent eggs being sterile without 

 renewed pairing of the hen. 



